Two pathways generate the bulk of ATP in animal cells -mitochondrial oxidative phosphorylation and glycolysis. Regulation of these ATP-generating processes is of fundamental interest to biologists, but these processes are difficult to study in cell lines, primary cells or tissue samples, especially in a 96-well configuration amenable to high throughput. Recently, Seahorse Bioscience has developed the XF24 Extracellular Flux Analyzer that permits serial measurements of O2 consumption and acid formation of cells cultured in 24-well plates. The flux analyzer enabled investigators to measure repetitively and non-destructively oxidative phosphorylation, glycolysis, nutrient utilization and other processes in single cell cultures. However, the 24-well instrument does not offer sufficient throughput for primary screening of large chemical libraries. Because primary cells or tissues need to examined in a limited time period, investigators using these samples are significantly limited to the number of variables that can be examined for a given animal. Accordingly, our specific aims are to 1) acquire a Seahorse 96-well Extracellular Flux Analyzer for measurement of O2 uptake and acid release, and 2) place this instrument in a multi-user environment that provides technical support, user training and applications expertise in support of individual user projects. This emerging technology will uniquely permit NIH-funded researchers working on a variety of projects to assess bioenergetics and metabolic responses in normal physiology and models of disease, including cancer, alcoholic hepatotoxicity, macular degeneration, heart ischemia and failure, multiple organ failure and diabetes. The results of those studies could lead to the development of new therapeutic treatments for some of these diseases.